Clofarabine Drug Information

Clofarabine injection is indicated for the treatment of pediatric patients 1 to 21 years old with relapsed or refractory acute lymphoblastic leukemia after at least two prior regimens.

Potential Concomitant Medications and Medications to Avoid

Consider prophylactic antiemetic medications as clofarabine injection is moderately emetogenic. Consider the use of prophylactic steroids to mitigate Systemic Inflammatory Response Syndrome (SIRS) or capillary leak syndrome (e.g., hypotension, tachycardia, tachypnea, and pulmonary edema). Minimize exposure to drugs with known renal toxicity during the 5 days of clofarabine injection administration since the risk of renal toxicity may be increased.

Non-hematologic Toxicity Withhold clofarabine injection if a patient develops a clinically significant infection, until the infection is controlled, then restart at the full dose. Withhold clofarabine injection for a Grade 3 non-infectious non-hematologic toxicity (excluding transient elevations in serum transaminases and/or serum bilirubin and/or nausea/vomiting controlled by antiemetic therapy). Re-institute clofarabine injection administration at a 25% dose reduction when resolution or return to baseline.

Discontinue clofarabine injection administration for a Grade 4 non-infectious non-hematologic toxicity. Discontinue clofarabine injection administration if a patient shows early signs or symptoms of SIRS or capillary leak syndrome (e.g., hypotension, tachycardia, tachypnea, and pulmonary edema) occur and provide appropriate supportive measures. Discontinue clofarabine injection administration if Grade 3 or higher increases in creatinine or bilirubin are noted.

Re-institute clofarabine injection with a 25% dose reduction, when the patient is stable and organ function has returned to baseline. If hyperuricemia is anticipated (tumor lysis), initiate measures to control uric acid.

Reconstitution/Preparation

Filter clofarabine injection through a sterile 0.2 micron syringe filter and then dilute with 5% Dextrose Injection, USP, or 0.9% Sodium Chloride Injection, USP, prior to intravenous infusion to a final concentration between 0.15 mg/mL and 0.4 mg/mL. Use within 24 hours of preparation. Parenteral drug products should be visually inspected for particulate matter and discoloration prior to administration, whenever solution and container permit.

Store diluted clofarabine injection at room temperature (15° to 30ºC). Discard unused portion in vial.

Clinical Trials Experience

Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice. The data described below reflect exposure to clofarabine in 115 pediatric patients with relapsed or refractory Acute Lymphoblastic Leukemia (ALL) (70 patients) or Acute Myelogenous Leukemia (AML) (45 patients). The median number of cycles was 2.

The median cumulative amount of clofarabine received by pediatric patients during all cycles was 540 mg. Most common adverse reactions (≥ 25%): vomiting, nausea, diarrhea, febrile neutropenia, pruritus, headache, bacteremia, pyrexia, rash, tachycardia, abdominal pain, chills, fatigue, anorexia, pain in extremity, hypotension, epistaxis, and petechiae. More detailed information and follow-up of certain events is given below.

Table 1: Most Commonly Reported (≥ 5% Overall) Adverse Reactions by System Organ Class N= The following adverse reactions were reported in < 5% of the 115 pediatric patients with ALL or AML: Gastrointestinal Disorders: cecitis, pancreatitis Hepatobiliary Disorders: hyperbilirubinemia Immune System Disorders: hypersensitivity Infections and Infestations: bacterial infection, Enterococcal bacteremia, Escherichia bacteremia, Escherichia sepsis, fungal infection, fungal sepsis, gastroenteritis adenovirus, infection, influenza, parainfluenza virus infection, pneumonia fungal, pneumonia primary atypical, respiratory syncytial virus infection, sinusitis, staphylococcal infection Investigations: blood creatinine increased Psychiatric Disorders: mental status change Respiratory, Thoracic and Mediastinal Disorder: pulmonary edema Table 2 lists the incidence of treatment-emergent laboratory abnormalities after clofarabine administration at 52 mg/m 2 among pediatric patients with ALL and AML (N=115).

Post-marketing Experience

The following adverse reactions have been identified during post-approval use of clofarabine. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure. Gastrointestinal disorders: gastrointestinal hemorrhage including fatalities.

Metabolism and nutrition disorders: hyponatremia Skin and subcutaneous tissue disorders: Stevens-Johnson syndrome (SJS), toxic epidermal necrolysis (TEN) (including fatal cases).

Pregnancy Risk Summary In animal reproduction studies, intravenous administration of clofarabine to pregnant rats and rabbits during organogenesis at doses approximately 0.2 to 1-times the maximum recommended human dose of 52 mg/m 2 based on body surface area (BSA) resulted in embryo-fetal mortality, alterations to growth, and structural abnormalities (see Data). Advise pregnant women of the potential risk to a fetus. There are no available data on clofarabine use in pregnant women to evaluate for a drug-associated risk of major birth defects, miscarriage, or adverse maternal or fetal outcomes.

Clofarabine should be used during pregnancy only if the potential benefits to the mother outweigh the potential risks, including those to the fetus. The estimated background risk of major birth defects and miscarriage for the indicated population is unknown. All pregnancies have a background risk of birth defect, loss, or other adverse outcomes.

In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is respectively. Developmental toxicity (i.e. reduced fetal body weights and increased post implantation loss) and increased incidences of external, soft tissue, and skeletal malformations and variations (including retarded ossification) were observed at 9 mg/kg/day (54 mg/m 2; approximately equivalent to the recommended human dose based on BSA). Altered ossification patterns (extra metacarpal or metatarsal ossification) were observed in single fetuses at lower doses of clofarabine (1 mg/kg/day and 3 mg/kg/day; 0.1- and 0.3-times the recommended human dose based on BSA).

Alterations in ossification patterns (increase in the average numbers of ossified thoracic vertebrae and rib pairs, and reduction in the average number of forepaw metacarpals) and abdominal wall defect were observed at 0.3 mg/kg/day (3.6 mg/m 2; 0.1-times the recommended human dose based on BSA).

Pediatric Use Safety and effectiveness have been established in pediatric patients 1 to 21 years old with relapsed or refractory acute lymphoblastic leukemia.

There were no known overdoses of clofarabine. In a Phase 1 study of adults with refractory and/or relapsed hematologic malignancies, the recommended pediatric dose of 52 mg/m 2 /day was not tolerated.